@article{oai:soar-ir.repo.nii.ac.jp:00011305, author = {堀内, 照夫}, journal = {信州大学農学部演習林報告}, month = {Mar}, note = {The effects of cobble stone on compressive strength of boulder concrete are observed using Chinese ball and mortar as a model. The results are summarized as follows: 1, The strength of boulder concrete is equal to pure concrete, if bond-strength between stone and mortar is similar to tensile strength of concrete. 2, The strength of boulder concrete increses with decreasing bond-strength between stone and mortar. 3, It is expectable that the cobble stone absorbs the load, if the stone connects with surrounding materials without any gap even poor bond-strength. 4, The influence of cobble stone diameter on the strength of boulder concrete decreases in proportion to the ratio of the test cylinder diameter to the cobble stone diameter, x. 5, If a gap rises in stone surface because of poor connection with mortar, the strength of the concrete decreses. It is suggested that the stress concentrates on the gap. 6, The ratio of the boulder concrete strength to the pure concrete strength, y, is shown by the function of the ratio x. y=1-1-a/x2 Here, a is a constant in variable number by a sort of cobble stone, and is the ratio of the stone strength to the concrete strength. The value of constant a is given as follows: 〓It is concluded that the compressive strength of boulder concrete is given in hatch of following figure as the surface roughness of cobble stone and the diameter ratio x., Article, 信州大学農学部演習林報告 5: 31-44(1968)}, pages = {31--44}, title = {玉石コンクリートの圧縮強度に及ぼす玉石の影響について(モルタルと石ボールによる実験)}, volume = {5}, year = {1968} }